Shifting the Population Debate:
Ending Overshoot, by Design & not Disaster
The need to #MoveTheDate

Every year Global Footprint Network marks Earth Overshoot Day, the day each year that humanity has
used up the planetary regenerative budget. In 2020, Earth Overshoot Day lands on August 22. 1
At Global Footprint Network, we envision a world where everyone thrives within the means of ourplanet’s ecological budget. We strive to get there by design, otherwise we will get pushed out ofovershoot by disaster, a process that will cause massive human suffering. Overshoot will end regardlessof our decisions. Our choice is how.
Through forward-looking decisions, we can turn around natural resource consumption trends while
improving quality of life for all. We have identified the five key areas 2 that are most forcefully defining
our long-term trends, all of which are shaped by our individual and collective choices:•

PLANET - How we help nature thrive: focus on conservation, restoration, regenerative use.
Given rapid erosion of biodiversity and ecosystem health, we need to protect nature since wevitally depend upon it.

•

CITIES - How we design and manage cities: encourage compact & integrated versus sprawling &
segregated cities. This determines both heating and cooling needs as well as mobility.

•

ENERGY - How we power ourselves: We phase out fossil fuels and bring in renewables and boost
efficiency. Energy currently makes up the biggest share of our overall Footprint.

•

FOOD - How we produce, distribute, and consume food: move to local, vegetable-based diets,
and away from industrial animal-based diets. Currently food production alone uses over half ofour planet’s biocapacity.

•

POPULATION - How many of us there are: key is to empower women and girls, and to make safe
and affordable family planning available to all. The larger our population, the less planet perperson. Empowering women is positive in itself. It also leads to smaller and healthier families
with more educational opportunities.

In this overview document we seek to highlight the significance of the “population factor.”
1

https://www.overshootday.org/2020-calculation/

The mathematical logic of these domains is simple. The “healthy planet” represents the supply side. The demandside is captured by the other four dimensions. Overall consumption is divided into two parts, food, and non-food.
The non-food dimension is what we call ‘cities’ – how we live, house ourselves, move about, and require products
and services. We also focus on energy, which is transversal to all domains. Since food, non-food, and energy isoften described in per-person terms to make it more accessible, we also have the population dimension to makethe assessment mathematically complete. This is the dimension discussed in this overview report.

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The significance of the population factor

Humanity currently demands 56% more from our planet than its ecosystems can renew. To maintain
85% of the world’s biodiversity, human demand can only use half of what the planet can provide. 3 Thismeans that current demand exceeds this goal by at least a factor of 3. 4
One of the most mathematically significant factors behind this growing imbalance is the steadily
increasing human population.
Figure 1 compares the development of the per person Ecological Footprint against biocapacity
availability per person and population growth. All current values are indexed against 1961. These
numbers demonstrate that the average per person Ecological Footprint over this time period has notchanged dramatically, even excluding the 2020 drop due to COVID-19.

Figure 1: Population, per person Footprint and per person biocapacity trends for the world. It
demonstrates how significant population expansion has been over the last 6 decades ascompared to average per capita demand (or Footprint).
3

https://www.half-earthproject.org/discover-half-earth/4

1.56 Earths / 0.5 Earths > 3

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While our National Footprint and Biocapacity Accounts conclude that our planet’s biocapacity has
slightly increased, according to UN statistics, boosted by the increase of agricultural productivities,
overall population growth has been much larger, leading to a shrinking over time of the biocapacity
available per person. 5 While the average per person Footprint has not changed much, this does not take
into account the vast differences in consumption among people. Nevertheless, even the grotesqueinequities we witness today do not change the conclusion that average per person resource
consumption has shifted far less over the last 6 decades than population numbers.

Still, there are powerful reasons not to talk about population

David Roberts explained in VOX that he is “an environmental journalist, but I never write about
overpopulation. Here’s why.” He concludes that “there’s much downside and not much upside to talking
about population.“ But how likely are we to succeed in not running down the planet without turning
around the population trend, especially if we advocate for high levels of human development for all?
How likely are we to succeed in turning the trends if we are not even able to talk about them?
Clearly, it is absolutely essential to start recognizing the ills of many population debates. A good example
to follow is the Sierra Club, which has started to recognize the reprehensible sides of its founders. There
are good reasons why progress in addressing the demographic factor has been slow. 6 Even as we
address the topic generously, with love and compassion, many pre-existing population debates havemade the discussions more difficult because of:•

A moralistic narrative (focusing on “what people should do”). Such narratives often trigger amoral combat debating “who is responsible” rather than a common inquiry about what would

The fact that Global Footprint Network’s National Footprint and Biocapacity Accounts show an increase of global
biocapacity over the last half century could be an exaggeration of reality. This is due to those accounts’ reliance on
UN data sets, which cover the increase of agricultural yields, but lack consistent accounting of degradation such as
soil erosion or groundwater depletion. Were they fully included would present an event tighter picture.

5

A friend wrote to us: “Living above our means is culturally engrained -- individually, nationally, and globally.
Helping people to break out of that and examine resource scarcity is an enormous challenge. For instance, asignificant piece is the question of motivation and how it affects certain outcomes. I've observed that when
predominantly male leaders decide to increase women's access to education and healthcare for population
reasons, they're often looking for the most cost-effective ways to get the desired result (smaller families) instead of
genuinely trying to create an even playing field. As a result, the dark side of human nature which led to horrendous
practices in the past hasn't gone away.

6

Given that reality, I think there's merit to the argument that when gender equality is motivated or justified bypopulation concerns, there are good reasons to be skeptical. Since it's possible to achieve the same results byframing gender issues in terms of human rights and economic progress, it's probably not worth it to dragpopulation and all its baggage into the mix.
Yet, it is also true that gender equality is a marginalized issue. Morally, I feel that the human rights case is thestrongest, but practically, I know deep down that the economic case is what political leaders care about. There area variety of other incentives to empower women, and population isn't really at the top of the list. Aging populations
seem to be a bigger concern – one that leads to policies that are boosting rather than reducing family sizes.”

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be best for all humans. By focusing on the responsibility question, the population dimension
gets rightly challenged by those pointing out that consumption levels also matter. But
sometimes, this truth is used to pit the consumption argument against population. This isunproductive and misses the point. 7 Rather, the debate needs to be framed around the benefitsof investing in smaller families. It needs to be explained around the ways that a shrinking
population contributes to securing the best lives possible for future generations everywhere.
•

Horrific past experiences. In the name of stabilizing population, inhumane policies and practices
including forced sterilizations have been imposed, particularly on women, and nearly all in lowincome populations. Many of these efforts have also been associated with eugenics. Rather, any
future action has to be in service of all people. Policies have to empower, work with, and listen
to women and low-income groups.

•

Economic fears that economic expansion, pension schemes, or relative economic power require
expanding populations, rather than recognizing that in an overused world, shrinking populations
can have a competitive advantage.

•

Insensitive to downright racist communications that are perceived as blaming the mostvulnerable, rather than compassionate communication that focuses on how all people,
particularly those with fewer economic possibilities, can be listened to and served best.

•

The wrong spokespeople. There has been an oversupply of older white men from high-income
countries advocating for the benefit of smaller populations. Rather, the main voices need to be
young people from around the world.

•Using off-putting trigger words. Successful communications NEVER advocate for “population
control” as it triggers unproductive debates and reignites old fears. It also reflects a wrong
approach. Effective approaches are never about some people controlling other people. Rather,
turning around demographic trends is all about empowerment and respect, including respectfor human life, future life, and the rest of the planet.

•

Being caught in “religious” or “ideological” debates that can easily lead to the amplification ofpolarizing, derailing, and unproductive “wedge issues”. 8 Examples include a singular focus onabortion, rather than sticking to broader principles and a language of true compassion. Religion
does not have to be a barrier, as demonstrated in Iran. Iran implemented a highly effective
demographic shift some decades ago that was home-grown and could not have been imposedfrom the outside.

For instance, often the point is raised that “one Bangladeshi has 10 times less Footprint than an American - who
has a population problem?” This narrative is based on the premise that sustainability is about allocating blame,
and that countries, regions and cities do not have skin in the game and are supposedly caught in a pure “tragedy ofthe commons”. Rather, the question is: What is the advantage for Bangladesh or for the US? See also comparisonof per person growth rates and population growth rates here.

7

Wedge issues are Issues that energize political support by driving emotionally charged divisions into public
opinions. See also https://en.wikipedia.org/wiki/Wedge_issue

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Page 4 of 11•Making population a singular issue that explains everything rather than embedding it in thelarger context of various factors contributing to ecological overshoot. Unsustainability is the sumof everything, and conversations about sustainability, rather than focusing on population only,
require recognizing the total realm of solutions that need to be implemented in order tosucceed.

•

False or absolute statements such as “population reduction is the only thing that matters” 9 or
“population reduction is the most effective way to combat climate change”, rather than using
accurate statements that recognize all factors. In the short term, investing in smaller families
has only social benefits and does not lead to immediate reductions in carbon emissions. For
instance, the need for 45% carbon emission reduction by 2030 (against 2010 levels), as
recommended by IPCC, cannot be achieved through population shifts alone, unless enormoustragedies - such as large portions of humanity dying off - unfold before then. In fact, for thistarget, shifts in population can only contribute a minor portion. However, over larger time
horizons, population shifts have the potential to outperform anything else. For example, if today
the world adopted German, Japanese, Spanish, Portuguese, or Italian reproduction rates, the2100 world population would be slightly above 4 billion, rather than 11.6 billion (median UN
projection) or 16 billion (upper UN projection). The implications for available biocapacity perperson are dramatic. Yet 2100 is not that far away: babies born today are expected to live
beyond 2100. 10

Global Footprint Network’s journey

Global Footprint Network has advocated for taking the population dynamic seriously, throughout theorganization’s history. The commitment has always been to fair, compassionate, and generous
strategies. In addition, we seek to recognize the pain that racist, sexist, and paternalistic approaches
have caused.
The question Global Footprint Network pursues is not “who is to blame?”, but given ecologicalconstraints, how can we best support those who will have to operate on this planet for many decades tocome. What are the most helpful scenarios for humanity so all can thrive within the ecologicalconstraints of the biosphere?
Global Footprint Network’s approach is consistent with the one proposed by Holdren, Ehrlich & Ehrlich,
which they called the IPAT approach, or what in climate debates is now often called the Kaya identity.
The Ecological Footprint translated this concept into real numbers using Ecological Footprint andbiocapacity accounts. 11 They capture all competing demands on the biosphere, and thereby illustrate
9

To put the entire weight of the sustainability transformation on population is unreasonable and not credible.

Global Footprint Network simple population cohort model, based on UN data allows one to calculate thepopulation implications of various fertility rates. It is a simplified model that builds on the UN statistics summarizedby five-year age segments. It also assumes constant age-specific mortality rates, and no shift in average age of
mother when child is born.
10

Most importantly, Global Footprint Network has consistently emphasized the population factor as a key
determinant. For instance, key to the National Footprint and Biocapacity Accounts is that they compare human

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the overall imbalance between human demand and what Earth can regenerate, as well as how thevarious factors have contributed to the overall demand.

Figure 2: Population, per person Footprint and per person biocapacity trends for four income
groups. None of the regions has had a more rapid increase in per person demand (Footprint)
than the population increased. This is not to deny that distributions within countries have been
grotesquely uneven.

demand against what is available. It is not helpful to just document per capita demand without showing that percapita supply is shrinking as well in most countries because population numbers are increasing faster than the
biological productivity of their ecosystems.

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Global Footprint Network’s approach counteracts the common perception that we are caught in a
“tragedy of the commons” where the right action is necessary for humanity, but little of the benefit
comes back to the individuals. In contrast, we demonstrate how sustainability actions have an
immensely positive effect on everyone involved.
What this makes evident is that rapid population growth in low-income countries hurts first andforemost the societies where the growth occurs, not humanity as a whole. For instance, rapid
population growth erodes the possibility of young people where the growth occurs, as it dilutes
educational opportunities, jobs, and quality health care.
Figure 2 shows the Footprint, biocapacity and population trends for country groups, organized byincome category. What is clear is that those with the least economic means exhibit the highest
population growth rates and a flat if not falling per person Ecological Footprint. Characterizing theacceleration of the demographic transition to be a noble, altruistic deed would be a misrepresentation.
It has so much potential to generate benefits to all involved.
Global Footprint Network has been working to help shift the discussion around population to becompassionate and productive. This has included helping larger organizations reframe their population
debate. For instance, we reintroduced the population discussion back into WWF over a decade ago in its
2008 Living Planet Report. Global Footprint Network also participated in a seminar on biologicalextinction at the Pontifical Academy of Sciences (2017), where about 1/3 of the time was occupied
discussing the population dynamic (the findings are now published in a Cambridge University book,edited by Peter Raven and Partha Dasgupta, called Biological Extinction).
Global Footprint Network’s most influential campaign, Earth Overshoot Day, reached 4.5 billion media
impressions in 2019 through 6’500 documented media stories in 120 countries (up from over 3 billion
media impressions the year before). Even Pope Francis commented on it. 12 The campaign emphasizes
the #MoveTheDate solution space with the five key domains mentioned, one of which is population.
This solution space is also the one to which our popular Footprint calculator points to. The calculator isvisited by over 3 million new people per year (and growing).
To explore this dilemma, we have invited a selection of predominately young people to present theirrespective perspectives on the population discussion. We even asked them whether it is productive tohave. You can see their diverse views here: https://www.overshootday.org/solutions/population/

Our trajectory is not merely fate

Making the case for embracing population topics and seriously and compassionately discussing thepositive impact of investments in turning the population trends, has been difficult. Even though it has
some of the highest, cost-effective long-term benefits, not just for the environment, but for health andeducational outcomes, it is also tightly linked to equal rights for all people independent of sex, gender,“The fact that has shocked me the most is yet another: The Overshoot Day […]. From July 30 we started toconsume more resources than the planet can regenerate in a year. It's very serious. It's a global emergency.” PopeFrancis in La Stampa.

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sexual orientation, age, etc., which we at Global Footprint Network would advocate for even if it had noenvironmental benefits.
One angle to emphasize is the economic argument – the link between shrinking populations andcompetitiveness. There is a strong misconception that growing populations are an economic advantage.
However, shrinking industrial populations have a better dependency ratio 13– meaning they can be
economically more cost-effective. In fact, using a simple spreadsheet-based population model, it is easy
to show that dependency ratios are more favorable in shrinking than in growing societies. Download the
spreadsheet here.
There are also many other benefits that GDP can hide. For example, ever higher housing costs becauseof crowding are not a real increase in wellbeing, even though they boost GDP (as the apparent “value”
of housing and the imputed rent amounts increase). In fact, in a truly sustainable society average
housing costs should not go up, just as houses should not be able to appreciate in value just by sitting
there. Appreciation only represents the ability of an older generation, who owned the real estate first,
to “tax” the larger younger generation who increasingly has to compete for the housing stock.
It is time to infuse some empowering facts into the public debate. We hope that our Ecological Footprint
analysis, including our simple population module, based on UN population statistics, can provide suchfacts to decision-makers. For instance, that there is a humane choice whether there will be 4 or 11
billion people sharing our planet in 2100. 14

The dependency ratio is that of the non-productive population (children and elderly) to the productive
population. As longevity increases, there may be an increasing need to also increase retirement age, something
reasonable given that older people are also healthier than in the past.
13

The mean age of first mothers is about 30 years in Portugal, and lifetime fertility (TFR total fertility rate) has
been as low as 1.23. Even if the mean age of mothers only increased 4 years, and fertility dropped to 1.5 children
per woman, a rate higher than in Portugal, Japan, Italy, Spain, or certain provinces in India (Kerala or Goa), we’d be
4 billion people by 2100 (babies born today have a good chance to be alive then). The current UN medianprojection is 11.6 billion. So, this makes a big difference to the possibility of those living in 2100. The calculation
spreadsheet to play with scenarios can be downloaded here.

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Appendix: additional materials

Calculation sheet for world population

Download a simple EXCEL Worksheet that allows you to run population projections based onassumptionshttps://www.overshootday.org/content/uploads/2020/08/population-cohort-model2020.xlsx of changed fertility rates, mortality and average age of mothers.
It is based on UN statistics from the past. It uses world average mortality rates, computed directly fromthe population statistics.
For feedback or interest in supporting a more sophisticated version, please contact
info@footprintnetwork.org and include POPULATION CALCULATOR in the subject line.

Possible questions for class discussions

1. What is holding back the conversation on the impact of population size on global overshoot?
Should we even have a conversation, or is it counterproductive?

2. If you were the head of the World Bank how would you approach the problem?
3. What are the main upsides and downsides of addressing population trends?
4. Is it fair to address population? Many say it is just about consumption. Or distribution.
5. Is there an economic advantage for a country to grow its population or could a shrinking one
have a competitive edge, particularly in times of global overshoot?
6. Which examples inspire you most?
7. Should this be a topic for a youth parliament?
8. Would it be okay to push back retirement as we continue to live longer, or is it better tocontinue growing the population in order to pay for retirement?
9. How does the topic of population link to your own life?
10. How can we make the topic of population inviting?

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Page 9 of 1111. Is it true that it is more about women rights than economic development that turns population
trends?
12. Is it reasonable to call population shrinkage cultural suicide?
13. How do you talk about population issues with friends?
14. Global Footprint Network and the Center for Biological Diversity produced Footprint condoms tobreak the ice in conversations. Is that offensive?
15. Which solutions do you think are most viable? Which ones least?
16. Is it morally acceptable to promote higher birth rates (as in the case of 66% of European
countries) in a time of massive ecological overshoot?
17. “Population control” is the wrong approach. After all, it is not about controlling people but
rather empowering them. Which words should we use? What is a good example you have seen?
18. What irks you when organizations talk about population? What irks you if they don’t?
19. What is the role of schools, health care, religious institutions, and NGOs to drive the population
topic?
20. How do you deal with the horrendous perspectives on population that have and still do
circulate, from racism to sexism and colonialism?
21. Is talking about population anti-human?
22. What solutions might work in your country? Check the case of Iran, a particularly interestingone.
23. Is birth control a human rights?
24. Is abortion a necessary topic within the population discussion? Or, is it a distraction?
25. What do you think about UN world population projections? Are they too limited and selffulfilling, given that Japanese/German/Italian fertility rates would lead to a 4 billion-strong
population by 2100 rather than nearly 11 billion as the UN median projection claims?

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Reflection on Lancet study of July 2020

With the prominence of the recent population projection paper published in The Lancet we would liketo contextualize the paper as it may have given rise to the idea that past population projections wereincorrect, or that a slow-down in population growth is of bigger concern than a growing population.
This is the paper:
Prof Stein Emil Vollset, DrPH, Emily Goren, PhD, Chun-Wei Yuan, PhD, Jackie Cao, MS, Amanda E Smith,
MPA, Thomas Hsiao, BS, et al. (2020) Fertility, mortality, migration, and population scenarios for 195
countries and territories from 2017 to 2100: a forecasting analysis for the Global Burden of Disease
Study. The Lancet. Published: July 14, 2020 DOI: https://doi.org/10.1016/S0140-6736(20)30677-2
Its main finding is that, according to its projections, global population would peak in 2064 and decline toby 8.8bn by 2100.
The environmental dimensions are treated quite superficially, with little recognition that a larger
population will require significantly more resources than a smaller population, and that future
populations will have to make do with no fossil fuel.
Robin Maynard, Executive Director of Population Matters, points at many weak spots in his assessment:"No one should be whooping with joy or pressing the panic button as a result of these projections- no population forecast can be relied on entirely. However, these do show that it is possible to
avoid the worst-case scenario of a global population growing into the next century, and they
offer hope of our numbers being more in line with what our planet can sustain - if we also
address the unsustainable consumption of the richest parts of the world.
"None of that can possibly come about unless we robustly pursue the policies that empower
people to choose smaller families, such as family planning and women's empowerment,
especially as investment in and delivery of those are currently under huge strain because of the
impacts of COVID-19. The authors rightly note the further, appalling danger that governments
may even restrict women's empowerment and reproductive freedom to address exaggerated
concerns about lower or ageing populations. We're already seeing that in Iran, and it's a subtext
in the rhetoric of nationalist, populist politicians from Hungary to Tanzania.
"Ageing populations and the economic risks and opportunities they signify must be planned forand can be planned for, without abusing people's rights, catastrophising and alarmism. We havethe ingenuity and resources to face demographic challenges. True catastrophe lies in a
population too big for our planet to sustain, with climate change uncontrolled, biodiversity
decimated, too little food and water for everyone's needs, and billions more trapped in poverty."
To Global Footprint Network, it is particularly surprising how much more concerned the authors seem tobe about the threat of having to restructure pension systems in high-income countries, rather than torecognize the plight of billions of people in countries with rapidly expanding populations being facedwith utterly brutal levels of resource insecurity.

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